Telephone apparatus



- (No Model.) a Sheets-Sheet 1.

E. B. 000K.

TELEPHONE APPARATUS.

Patented Feb. 1, 1898.

' a SheetsSheet 2. P. B. 000K.

' ,TELEPHONE APPARATUS. No. 598,285. A Patented Feb. 1,1898.

4 L I w Q (No Model.)

3 Sheets-Sheet 3. F B 000K TELEPHONE APPARATUS.

No. 598,285. Patented Feb. 1,1898

PATENT rrrcn.

FRANK l3. COOK, OF CHICAGO, ILLINOIS.

TELEPHONE APPARATUS.

SPECIFICATION forming part of Letters Patent No. 598,285, dated February 1, 1898.

Application filed March 25, 1895. Renewed December 16, 1897. $erial No. 662,209. (No model.)

My invention relates to certain improvements in apparatus designed for use in connection with telephone-switchboards.

In telephone systems it often becomes necessary to connect a ground-circuit or a circuithaving a return in common with other circuits with a complete metallic circuit. When such circuits are connected together, the metallic circuit is then, as it is termed, thrown out of balance, causing the circuits, both the metallic circuit and ground, to become noisy and interfere with conversation, especially when the metallic circuit is of considerable length. To overcome this condition, it has been usual to employ a repeating-coil and to include the same in the connecting-cord of the plugs by which connection is established between subscribers on the switchboard. The disadvantages resulting from the inclusion of the repeating-coil in the plugs and cords resides in the fact that the operator answers a call with the ordinary plug and cord having no repeating'coil included and establishes the connection between a grounded circuit and a metallic circuit with this ordinary cord and plug. Upon discovering that the circuit is noisy, by reason of such connection,it has been necessary for the operator to momentarily break the connection and substitute a cord and plug including a repeating-coil for the ordinary plug and cord. To overcome these disadvantages, it is the object of my invention in this respect to provide supplemental or auxiliary spring-jacks in addition to the springjacks which are employed to effect a connection between two different circuits, these supplemental jacks being mounted upon the switchboard and each line terminating at the switchboard having one of these supplemental jacks included therein. In other the repeating-coil into that line.

provide a cord-circuit including therein a repeating-coil and having a plug which is adapted for insertion in the supplemental springjack and which when inserted in any one of said supplemental spring-jacks in effect loops If, for instance, it is desired to ring out over the ground-circuit, the repeating-coil may be looped into the metallic circuit, and thus the necessity of ringing through the resistance of the repeating-coil avoided. In this arrangement the operator receives the call and establishes the connection between the subscribers in the ordinary manner, and upon discovering that the line is out of balance, making it noisy, the operator then simply includes the repeating-coil in the circuit by inserting the plug of the repeatingcoil in either one of the supplemental spring-jacks.

In the operation of telephone-switchboards it is desirable that the head-telephone may be made capable of movement from point to point with the operator relative to different points on the switchboard, in order that the operator may make connections between the head-telephone and various sections of the switchboard. It is also desirable that both the head-telephone and the transmitter constituting the operators telephone set may be capable of being moved from point to point in the same manner. It is desirable also that the battery-circuit of the switchboard-transmit ters should remain open when the transmitters'are not in use. This latter result has heretofore been accomplished by means of a manually-operated switch, whereas it is the object of the present invention, in this respect, to accomplish this result automatically.

My invention has for a further object the provision of certain details of construction in annunciator-drops and also relates to certain improved construction of switchboards.

Reference may now be had to the accon1 panying drawings, in which Figure 1 is a plan view of my improved double spring-jack switch for use in conjunction with a portable head-telephone or operators set. Fig. 2 is a central longitudinal section of said jack Fig. 3.is a cross-section on the line y y of Fig. 2. Fig. 4 is a plan View of a special form of plug used in connection with the jack shown in the preceding figures.

Fig. 5 is a longitudinal section on the line 2' z of Fig. 4. Fig. 6 is an end view of the plug. Fig. 7 is a view of the opposite side of the plug, showing the diagonal connection. Fig. 8 is a View similar to Fig. 1 of the supplemental repeating-coil spring-jack. Fig. 9 is a central longitudinal view through the jack, partly broken away to show the spring-contact. Fig. 10 is an end view of the jack. Fig. 11 is a plan view of the form of plug used with the supplemental repeating-coil jack and to which the repeating-coil is permanently connected. Fig. 12 is a longitudinal section on the line a a of Fig. 11. Figs. 13 and 14 are respectively front and rear end views of the plug. Fig. 15 is a diagrammatic representation of the spring-jack and plug shown in Figs. 1 to 7, inclusive, and of the circuits including the operators set, this view illustrating the means of connecting a portable head telephone and transmitter with the switchboard. Fig. 16 is a like view showing the arrangement by which a portable headtelephone and the fixed transmitter is connected with the switchboard. Fig. 17 is a view similar to Figs. 15 and 16, showing the means of connecting the repeating-coil with the supplemental repeating-coil jack shown in Figs. 8 to 14, inclusive. Fig. 18 is a perspective view of the front of an annunciatordrop, partly broken away to show the contacts. Fig. 19 is a front view of a portion of switchboard, showing removable and replaceable sections. Fig. 20 is a front or edge elevation of one removable and replaceable section shown removed. Fig. 21 is a side view of the same. Fig. 22 is arear edge elevation of the same.

Referring first to the construction and arrangement of what may be termed an operators cut-out, whereby a portable head-telephone or a portable operators set may be connected with the switchboard, the referencenumeral 25 in Figs. 1, 2, and 3 designates as a whole the special form of spring-jack used for this purpose, and the reference-numeral 26 in Figs. 4, 5, and 6 likewise designates as a whole the form of plug employed, it being understood that the usual covering sleeve or handleistobesupplied. Thespring-jack25comprises in its construction the frame 27 and the two pairs of spring contact-strips 28 and 28 and 29 and 29, these strips being all insulated one from the other and from the frame, so that circuits connected with the strips are open when no plug is in the jack. The special form of plug used con junctively with this jack consists of a pair of extensions 30 and 31, of insulating material, projected from the body-plate 32, which is likewise of insulating material. Extended through the body-plate 32 and the extensions 30 and 31 are conducting-wires 33 and 33 and 34 and 34, arranged in pairs vertically in the extensions, said extensions being cut away at their extremities in order to expose the ends of the said con- .coil 37.

end of the plug 26. At the other end of the plug are suitable terminals for connecting the flexible conducting-cords mounted upon the plate 32 and connected with the conducting-wires 33, 33, 34, and 34.

In Figs. 15 and 16 the circuit arrangement is illustrated.

In Fig. 15 is shown the connections and disposition of apparatus when both the headtelephone and transmitter are portable.

The battery is designated at 35 included in a circuit 36, connected to the contact-strip 29' of the jack 25 and extended to and also connected with the contact-strip 28 of the said jack, which circuit also includes the primary of the induction-coil 37. The lead 38 to the switchboard is connected to the contact-strip 29, and the secondary of the induction-coil 37 is included in this lead. The other lead 39 to the switchboard is connected to the contact-strip 28. The lead 40, including the transmitter 41, is connected with the contactpoint 34 of the plug 26 at one end and to the contact-point 33 of said plug at the other. The

lead 42, including the head-telephone 43, is connected at one end to the contact-point 34 and at the other end to the contact-point 33. The plug 26 being inserted into the springjack 25, as shown in Fig. 15, the circuit of the transmitter 41 is through the contacts 33 and 34 of the plug and the contact-strips 28 and 29 of the jack to the circuit 36, including the battery 35 and the primary of the induction- The head-telephone 43 is connected, through the contacts 33 and 34 of the plug, with the contact-strips 28 and 29 of the jack and thus with theleads 38 and 39 to the switchboard, one of which leads, 38, includes the secondary of the induction-coil.

In the instance illustrated in Fig. 16 the telephone-transmitter 41 islocated in one permanently-fixed position and included in the circuit 36, connected with the contact-strips 28 and 29 of the jack, the contact-points 33 and 34 of the plug being connected together by a short wire 44. (Shown also in Fig. 8.) It will be observed that when no plug is in any spring-jack the battery-circuit is open, as all of the contact-strips of the jacks are insulated from each other and from the frame of the jack, and thus the energy of the battery is conserved. A slight examination of these circuits will show that it is immaterial in practice which of the two positions of the plug in the spring-jack is chosen, inasmuch as the proper circuit is used in either case because of the diagonal arrangement of the plug-terminals and spring-jacks.

The advantages to be attained by the use of this apparatus are several. First, a considerable saving of current which would otherwise be wasted is effected, this applying to all telephone-exchanges during such hours as the number of operators is less than the number of operators equipments, and still more particularly to smaller exchanges where the ducting-wires to provide four contacts at the operators circuit is not continuously in use.

at any desired position.

Second, it enables any given operator to move from position to position upon the switchboard without the necessity of using a different head-telephone at each position, inasmuch as by means of this apparatus the same portable head-telephone may be worn and connected at will with theswitchboard-circuit This apparatus allows also, when desired, the use of a portable receiver and transmitter which may at will be connected to or disconnected from the switchboard-circuit at any position, thereby rendering the operator able to move from position to position, as before described, carrying the entire portable telephone equipment.

Referring to the arrangement of circuits and construction of apparatus whereby the repeating-coil is included in the line of any circuit, the reference-numeral 5O designates as a whole in Figs. 8, 9, and 10 the special form of supplemental repeating coil jack which is used for this purpose, and in Figs. 11, 12, 13, and 14 the plug 51 is illustrated and shown without the usual sleeve or handle. This plug, however, differs only from the plug'26 in exterior dimensions and arrangement for connections, and it therefore. has the conductingwires 52, 52, 53, and 53, which terminate in contact-points at one end of the plug and are connected to flexible-conducting-cord terminals at the .other, which cords include the repeating-coil 55.

The supplemental spring-jack 50 is similar in construction to the spring-jack 25 and has the contact-strips 56 and 56 and 57 and 57. These contact-strips are connected electrically together normally by means of the conducting contact-pins 58, and therefore circuits connected with saidcontact-strips of the jack are closed through the jack.

Referring to Fig. 19, which shows the front of a switchboard, the supplemental repeating-coil spring-jacks 50' are shown disposed in proximity to and above the ordinary springjacks 59, each line terminating in the switch-- board being provided with oneof the said supplemental spring-jacks 50. The lines 60 and 61, leading from a given subscribers station, are connected to the contact-strips 56 and 57 of the supplemental jack 50, and the ordinary spring-jack 59' and calling-drop 62 are connected by the leads 63 and'64 with the contact-strips 56 and 57 of the supplemental jack 50. WVhen the plug 51 is inserted in the supplemental spring-jack 50, the circuit is as follows: From the line 60 through the contact-strip 57of the jack to the contact 53 of the plug, through one side of the repeatingcoil 55 to the contact-point 52 of the plug to the spring 56 of the jack, and thence to the line 61. The other side of the circuit is from and through the main spring-jack 59 to lead 63, to contact-spring 56 of the jack, contactpoint 52 of the plug, through the other side of the repeating-coil 55 to contact-point 53 of the plug and the contact-strip 57 of the jack to the lead 64:.

From the foregoing description it is evident that the operator upon receiving a call establishes the connection desired with an ordinary cord and plug in the usual manner by means of the ordinary spring-jacks 59, which I will term the main spring-jacks. Upon discovering that the circuit is noisy, as a result of connecting a ground-circuit with a metallic circuit, the operator includes or loops into the circuit, consisting of the ground and metallic circuits connected together, a repeating-coil by inserting a repeating-coil plug 51 into either one of the supplemental repeating-coil spring-jacks 50 of that connected circuit. It is difficult, and in some cases impractical, to ring or extend a signaling-current through the resistance of a repeating-coil, and therefore the operator may include the repeating-coil in the line of the subscriber extending the call, as the ringing signal-current is then to be extended over the line of the subscriber to be called.

In Fig. 18 I have shown the front portion of an annunciatordrop which is provided with contact-points, whereby to close a local circuit as the drop falls. The shutter of the drop is hinged and held in the usual manner and carries a lug 71 on its lower end, which bears against a contact-spring 72. A contactpoint 73 is so located that when the dropshutter falls the lug 71 presses the contactspring into contact with the contact-point 7 3. I provide an insulating block or stud 7 4, which is slotted and so positioned upon the base 75 as to inclose the contact-point 73 and the contact-spring 72, thus insulating said contact-point and protecting the contactspring. 1

Referring to the sectional switchboard shown in Figs. 19 to 22, inclusive, a frame 80 is provided adapted to inclose each one of the removable and replaceableindividual sections 81, which sections carry the necessary springjacks and annunciators or other suitable apparatus, including a plug and conductingcord.

The parts above described are assembled as shown in the drawings, and, in connection with proper conducting-wires, ringing-keys, spring-jacks, ann-unciator, and cam-lever or equivalent mechanism, form an individual section which is complete in itself, being equipped with all the apparatus necessary to connect the circuit of that section with any other circuit, and when assembled with otl1- ers similar and an operators telephone equipment properly connected to all produce a complete telephone-switchboard,it being only necessary to provide some suitable form of table or framework to support the whole. If this framework be built of sufficiently great capacity, sections of the style described and illustrated may be from time to time added, thus increasing. the capacity'to any desired number within the limit of the framework. It is to be understood of course that the sections may be equipped with any suitable apparatus and still employ the feature of .my invention, which consists in the provision of these removable and replaceable sections.

In Figs. 20 and 21 is shown a pulley-weight 82, consisting of the pulley-weight 83, about which the flexible conducting-cord 84 is extended. The frame or block 85 of the pulley constitutes the bulk of the weight and is about equally disposed both above and below the pulley, thus differing from the ordinary pulley-weight, where the weight is all located below the pulley. This distribution of the weight about the pulley is a distinct advantage as I employ it, because not only is the pulley-weight better balanced, but greater length of cord is obtained for making connections than would be otherwise. The weights do not move up and down in a perpendicular line, but, in order to provide more space for the operators feet, are moved on an inclined plane, this result being accomplished by means of two guide-wires 86 and 87, the pulley-weight being between the two wires and guided by them. These wires are secured to the keyboard at one end and held in place by means of the extension 88, secured to the keyboard, which extensions have flat springs 89 connected to their lower ends. The other ends of the guide-wires are connected to the springs 89, which are thus automatically held constantly under tension.

Throughout the foregoing specification in describing the apparatus whereby the repeating-coil is included in a connected circuit referencehas been had to the connection of a ground-circuit with a complete metallic circuit. I do not desire to be understood as having limited my invention to such a condition only, as it is evident that what is known as a complete metallic circuit may be accidentally connected with ground, and the same therefore becomes in fact a ground-circuit,

so that if a metallic circuit were connected with a circuit in such a condition the use of a repeatin g-coil would be necessary if the metallic circuit so connected were of a considerable length.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is-

1. In a telephone-switchboard a plurality of line-circuits converging at said board, a series of main spring-jacks, one for each circuit, by which the connections are established between the different line-circuits by means of main cords and plugs and a series of auxiliary or supplemental spring-jacks, one for each of said circuits, together with a repeating-coil included in a supplemental cord-circuit having a supplemental plug whereby the repeating-coil may be looped and included in any one of the circuits aforesaid, terminating at the switchboard, by insertion of the supplemental plug in either one of the supplemental spring-jacks of the connected circuit.

2. The combination in a telephone-switchboard of a plurality of line-circuits converging at said board, a series of main spring-jacks, one for each circuit, by which the connections are established between the different line-circuits, by means of the main cords and plugs and a series of auxiliary or supplemental the contact-points of each pair, and the other 7 side of the repeating-coil connected to the remainin g contact-points of each pair, whereby, when the supplemental plug is inserted in the supplemental jack, the repeating-coil is included in the circuit of that jack.

3. In atelephone-switchboard an operators telephone-circuit including a portable headtelephone, a spring-jack switch mounted upon the switchboard, a plug with which the cords from the head-telephone are connected, by which the telephone-circuit is completed by the act of inserting the plug in the springjack switch and a local circuit, including a battery and transmitter which is also completed by the act of inserting the plug in the spring-jack.

4. In a telephone-switchboard an operators telephone-circuit including a portable headtelephone, a spring-jack switch mounted upon the switchboard, a plug with which the cords from the head-telephone are connected, by which the telephone-circuit is completed by the act of inserting the plug in the springjack, a local circuit, a battery, and the primary of the induction-coil, included in said local circuit and connected with the springjack, and a portable transmitter also included in said local circuit but connected with the plug, whereby the local circuit and telephonecircuit are completed also by the act of inserting the plug in the spring-jack.

5. In a telephone-switchboard an operators telephone-circuit, including a telephone, a local circuit including a battery and transmitter, a spring jack comprising double switches one of which is connected with a portion of the telephone-circuit to the switchboard and the other with a portion of the local circuit and a twin or double plug connected with the remaining portion of the 10- cal circuit, and the telephone-circuit whereby the act of inserting the plug in the spring-jack unites the difierent portions of the telephone and local circuits, and closes the normally open switches of the spring-jack.

6. A sectional switchboard consisting of a frame and removable and replaceable switchboard-sections, each one of which is equipped with suitable apparatus including cords, plugs and switches,whereby each section may rzo be connected by the apparatus mounted on S. An annunciator-drop consisting of a said section, to any other section or other front plate carrying the hinged drop of the switches. annunciator and a slotted insulator-block 7. In a telephone-switchboard and in comalso secured to said front plate Within which I5 5 bination with the flexible cord conductors the contacts are disposed.

thereof, a pulley-Weight in the bight of the "In testimony whereof I affix my signature cord acting as a take-up for said cords, and in presence of two witnesses.

guides upon which the pu11ey-weights travel, FRANK B. CO 01K. together with automatically-operating yield- Witnesses: 10 ing pressure devices fixed at one end and se- CHAS. O. BULKLEY,

cured at the other to the guides. L. W. BULKLEY. 

